US7863614B2 - LED backlight device and LCD device - Google Patents

LED backlight device and LCD device Download PDF

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Publication number
US7863614B2
US7863614B2 US12/230,229 US23022908A US7863614B2 US 7863614 B2 US7863614 B2 US 7863614B2 US 23022908 A US23022908 A US 23022908A US 7863614 B2 US7863614 B2 US 7863614B2
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substrate
led
film layered
backlight device
thin
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US20090073350A1 (en
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Hiroshi Toyama
Yukio Nakamura
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Oki Electric Industry Co Ltd
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Oki Data Corp
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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133603—Direct backlight with LEDs
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133611—Direct backlight including means for improving the brightness uniformity
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133605—Direct backlight including specially adapted reflectors
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133614—Illuminating devices using photoluminescence, e.g. phosphors illuminated by UV or blue light

Definitions

  • This invention relates to an LED backlight device and an LCD device having the LED backlight device.
  • a general LCD (Liquid Crystal Display) device is configured to irradiate an LCD panel with a light emitted by a light source, and to change alignments of liquid crystals arranged on the LCD panel so as to display an image using the light passing through the LCD panel.
  • the light source used in such an LCD device is called as a backlight, since the light source is disposed on a backside of the LCD panel (i.e., a side opposite to a display surface of the LCD panel).
  • the conventional light source is composed of a cold cathode ray tube or a semiconductor light emitting element.
  • the light source using the semiconductor light emitting element has been broadly used, since such a light source has a long lifetime and contributes to reduction of power consumption.
  • a conventional surface-emitting light source using an LED (Light Emitting Diode) as the above described semiconductor light emitting element and a plate-like member called as a light guiding plate (or a light diffusion plate) for guiding the light emitted by the LED.
  • the light emitted by the LED is incident on an end surface of the light guiding plate, and reflected and diffused in the direction perpendicular to a surface of the light guiding plate (see, Japanese Laid-Open Patent Publication No. 11-232920).
  • the light diffused in the light guiding plate tends to attenuate due to the reflection and diffusion, as a distance from the incident surface (i.e., the end surface of the light guiding plate) increases. Therefore, in order to obtain a high light intensity uniformly over the entire surface, the structure of the light guiding plate needs to be complicated, and the LED backlight device needs to be thick.
  • the present invention is intended to solve the above described problems, and an object of the present invention is to provide an LED backlight device which is thin and provides a high light intensity, and an LCD device using such an LED backlight device.
  • the present invention provides an LED backlight device including a first substrate having optical transparency and having a first surface and a second surface opposite to the first surface.
  • An LED thin-film layered structure is fixed to the first surface of the first substrate.
  • the LED thin-film layered structure is formed of epitaxially grown inorganic material layers as a P-N junction device.
  • An anode electrode and a cathode electrode are provided on the LED thin-film layered structure.
  • An anode driver IC and a cathode driver IC are provided for driving the LED thin-film layered structure.
  • An anode wiring is provided on the first surface of the first substrate for electrically connecting the anode driver IC and the anode electrode of the LED thin-film layered structure.
  • a cathode wiring is provided on the first surface of the first substrate for electrically connecting the cathode driver IC and the cathode electrode of the LED thin-film layered structure.
  • a phosphor is provided on the second surface of the first substrate.
  • a second substrate has optical transparency and has a first surface and a second surface opposite to the first surface. The first surface of the second substrate faces the first surface of the first substrate.
  • a reflection layer is provided on the second surface of the second substrate.
  • the thickness of the LED backlight device can be reduced, and the light intensity of the LED backlight device can be increased.
  • the present invention also provides an LED backlight device including a first substrate having optical transparency and having a first surface and a second surface opposite to the first surface.
  • An LED thin-film layered structure is fixed to the first surface of the first substrate.
  • the LED thin-film layered structure is formed of epitaxially grown inorganic material layers as a P-N junction device.
  • An anode electrode and a cathode electrode are provided on the LED thin-film layered structure.
  • An anode driver IC and a cathode driver IC are provided for driving the LED thin-film layered structure.
  • An anode wiring is provided on the first surface of the first substrate for electrically connecting the anode driver IC and the anode electrode of the LED thin-film layered structure.
  • a cathode wiring is provided on the first surface of the first substrate for electrically connecting the cathode driver IC and the cathode electrode of the LED thin-film layered structure.
  • a phosphor is provided on the second surface of the first substrate.
  • a second substrate has a first surface and a second surface opposite to the first surface. The first surface of the second substrate faces the first surface of the first substrate.
  • a protrusion is provided on the first surface of the second substrate so as to face a position on the first surface of the first substrate apart from the LED thin-film layered structure by a certain distance. The protrusion has an inclined surface.
  • a reflection layer is provided to cover the first surface of the second substrate and the protrusion.
  • the present invention also provides an LED backlight device including a first substrate having optical transparency and having a first surface and a second surface opposite to the first surface.
  • An LED thin-film layered structure is fixed to the first surface of the first substrate.
  • the LED thin-film layered structure is formed of epitaxially grown inorganic material layers as a P-N junction device.
  • An anode electrode and a cathode electrode are provided on the LED thin-film layered structure.
  • An anode driver IC and a cathode driver IC are provided for driving the LED thin-film layered structure.
  • An anode wiring is provided on the first surface of the first substrate for electrically connecting the anode driver IC and the anode electrode of the LED thin-film layered structure.
  • a cathode wiring is provided on the first surface of the first substrate for electrically connecting the cathode driver IC and the cathode electrode of the LED thin-film layered structure.
  • a protrusion is provided on a position on the first surface of the first substrate apart from the LED thin-film layered structure by a certain distance. The protrusion has an inclined surface.
  • a phosphor is provided on the second surface of the first substrate.
  • a second substrate has optical transparency and has a first surface and a second surface opposite to the first surface. The first surface of the second substrate faces the first surface of the first substrate.
  • a reflection layer is provided on the second surface of the second substrate.
  • FIG. 1 is a side sectional view showing an LED backlight device according to the first embodiment of the present invention
  • FIG. 2 is a perspective view showing a first substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a first surface side thereof;
  • FIG. 3 is a perspective view showing the first substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a second surface side thereof;
  • FIG. 4 is a perspective view showing a second substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a second surface side thereof;
  • FIG. 5 is a side sectional view showing an LCD device using the LED backlight device according to the first embodiment of the present invention
  • FIG. 6 is a schematic view showing a process for peeling an LED thin-film layered structure according to the first embodiment of the present invention
  • FIG. 7 is a schematic view showing a process for fixing the LED thin-film layered structure to a surface of a substrate according to the first embodiment of the present invention
  • FIG. 8 is a schematic view showing a process for dividing the LED thin-film layered structure into a plurality of LEDs according to the first embodiment
  • FIG. 9 is a side sectional view showing an LED backlight device according to the second embodiment of the present invention.
  • FIG. 10 is a perspective view showing a second substrate of the LED backlight device according to the second embodiment of the present invention, as seen from a first surface side thereof;
  • FIG. 11 is a side sectional view showing an LED backlight device according to the third embodiment of the present invention.
  • FIG. 12 is a perspective view showing a first substrate of the LED backlight device according to the third embodiment of the present invention, as seen from a first surface side thereof;
  • FIG. 13 is a side sectional view showing an LED backlight device according to the fourth embodiment of the present invention.
  • FIG. 14 is a perspective view showing a first substrate of the LED backlight device according to the fourth embodiment of the present invention, as seen from a first surface side thereof, and
  • FIG. 15 is a perspective view showing a second substrate of the LED backlight device according to the fourth embodiment of the present invention, as seen from a second surface side thereof.
  • FIG. 1 is a side sectional view showing an LED backlight device according to the first embodiment of the present invention.
  • FIG. 2 is a perspective view showing a first substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a first surface side thereof.
  • FIG. 3 is a perspective view showing the first substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a second surface side thereof.
  • FIG. 4 is a perspective view showing a second substrate of the LED backlight device according to the first embodiment of the present invention, as seen from a second surface side thereof.
  • FIG. 5 is a side sectional view showing an LCD device using the LED backlight device according to the first embodiment of the present invention.
  • an LED backlight device 100 and an LCD panel 200 constitute an LCD device according to this embodiment.
  • the LED backlight device 100 is disposed on a backside of the LCD panel 200 having a display surface 201 on a front side, and functions as a light source.
  • the LED backlight device 100 includes a substrate 10 (i.e., a first substrate) in the form of a flat plate.
  • the substrate 10 has a first surface 10 a (i.e., an upper surface in FIG. 1 ) and a second surface 10 b (i.e., a lower surface in FIG. 1 ).
  • LEDs 11 i.e., LED thin-film layered structures
  • a phosphor 30 is fixed to the second surface 10 b of the substrate 10 .
  • the LED backlight device 100 includes a substrate 40 (i.e., a second substrate) in the form of a flat plate.
  • the substrate 40 has a first surface 40 a (i.e., a lower surface in FIG. 1 ) that faces the substrate 10 and a second surface 40 b (i.e., an upper surface in FIG. 1 ).
  • a reflection layer 41 is fixed to the second surface 40 b of the substrate 40 so that the reflection layer 41 entirely covers the second surface 40 b as shown in FIG. 4 .
  • the first surface 10 a of the substrate 10 and the first surface 40 a of the substrate 40 face each other.
  • a plurality of LEDs 11 are arranged in an array on the first surface 10 a of the substrate 10 as shown in FIG. 2 .
  • the number and arranging manner of the LEDs 11 can be determined arbitrarily.
  • LEDs 11 are described so that 9 LEDs 11 are arranged in a square grid having three rows and three columns, for convenience of illustration.
  • an anode driver IC 31 and a cathode driver IC 32 for driving the LEDs 11 are disposed on the first surface 10 a of the substrate 10 .
  • the anode driver IC 31 is connected to ends of lines of the anode wiring 12 connected to the anode electrodes 14 of the endmost LEDs 11 closest to the anode driver IC 31 of the respective columns.
  • the cathode driver IC 32 is connected to an end of the cathode wiring 13 connected to the cathode electrodes 15 of the endmost LEDs 11 farthest from the anode driver IC 31 of the respective columns.
  • each column the anode electrodes 14 and the cathode electrodes 15 of the adjacent LEDs 11 are connected to each other by interconnection wirings 21 .
  • the LEDs 11 of each column are connected in series via the interconnection wirings 21
  • the anode electrode 14 of the endmost LED 11 in each column and the cathode electrode 15 of the endmost LED 11 in each column are respectively connected to the anode driver IC 31 and the cathode driver IC 32 via the anode wiring 12 and the cathode wiring 13 .
  • the substrates 10 and 40 are formed of quarts plate or glass plate having optical transparency, or resin plate (composed of, for example, acrylic resin) having optical transparency.
  • the reflection layer 41 is composed of material reflecting near-ultraviolet rays or ultraviolet rays such as metal film (for example, aluminum) or multilayered reflection film formed using vacuum deposition method, plating method or the like.
  • the phosphor 30 emits white light when exposed to near-ultraviolet rays or ultraviolet rays.
  • the phosphor 30 is coated on the second surface 10 b of the substrate 10 as shown in FIG. 3 .
  • the phosphor 30 can be formed by mixing a phosphor that emits red light when exposed to near-ultraviolet rays or ultraviolet rays, a phosphor that emits green light when exposed to near-ultraviolet rays or ultraviolet rays and a phosphor that emits blue light when exposed to near-ultraviolet rays or ultraviolet rays.
  • the phosphor that emits red light is, for example, Y 2 O 2 :Eu or (Y, Gd) BO 3 :Eu.
  • the phosphor that emits green light is, for example, LaPO 4 :Ce, Tb or Zn 2 SiO:Mn.
  • the phosphor that emits blue light is, for example, (Sr, Ca, Ba, Mg) 5 (PO 4 ) 3 Cl:Eu or BaMgAl 10 O 17 :Eu.
  • These phosphor materials are dispersed in a sealant composed of silicone-based resin having optical transparency, and the resultant material is coated and dried, so that the phosphor 30 is obtained.
  • the phosphor that emits red light is not limited the above described material, but can be composed of any kind of material that emits light having the wavelength in the range from 620 nm to 710 nm when exposed to near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 nm to 450 nm.
  • the phosphor that emits green light can be composed of any kind of material that emits light having the wavelength in the range from 500 nm to 580 nm when exposed to near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 nm to 450 nm.
  • the phosphor that emits blue light can be composed of any kind of material that emits light having the wavelength in the range from 450 nm to 500 nm when exposed to near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 nm to 450 nm.
  • the material and coating method of the phosphor 30 can be arbitrary and suitably selected in accordance with the configuration of the phosphor 30 , and are not limited to the above described material and coating method.
  • the substrate 10 has a surface layer 101 (having optical transparency) forming the first surface 10 a , and the surface layer 101 is formed of organic insulation film (such as polyimide film or the like) or an inorganic insulation film.
  • the surface layer 101 is planarized to a surface accuracy less than or equal to several tens of nanometers.
  • the LEDs 11 are peeled off from another substrate (i.e., a base material) as described later, and are fixed to the surface layer 101 of the substrate 10 by means of intermolecular force such as hydrogen bonding, so that the LEDs 11 are integrated with the substrate 10 .
  • the surface layer 101 is shown in side sectional view only, and omitted in other figures.
  • Each of the LEDs 11 is a thin-film LED that emits near-ultraviolet rays or ultraviolet rays, and is composed of a thin-film layered structure having a heterostructure or a double-heterostructure formed by epitaxially growing inorganic material such as gallium nitride, gallium indium nitride, aluminum gallium nitride, aluminum nitride or the like.
  • the LED 11 is not limited to the above described material, but can be composed of any kind of material that emits near-ultraviolet rays or ultraviolet rays, more preferably, the light having the wavelength in the range from 300 to 450 nm.
  • the LEDs 11 and the phosphor 30 are respectively formed on the first and second surfaces 10 a and 10 b of the substrate 10 so that the LEDs 11 and the phosphor 30 face each other. Further, the LEDs 11 and the reflection layer 41 are respectively formed on the first surface 10 a of the substrate 10 and the second surface 30 a of the substrate 40 so that the LEDs 11 and the reflection layer 41 face each other.
  • the phosphor 30 and the reflection layer 41 are disposed so as to face each other on both sides of the LEDs 11 via the substrates 10 and 40 . Therefore, near-ultraviolet rays or ultraviolet rays emitted by the LEDs 11 in the direction toward the substrate 10 are incident on the phosphor 30 as shown by arrows A in FIG. 1 . Near-ultraviolet rays or ultraviolet rays emitted by the LEDs 11 in the direction toward the substrate 40 are reflected by the reflection layer 41 as shown by arrows C in FIG. 1 , and are incident on the phosphor 30 .
  • the phosphor 30 (facing the LEDs 11 and the reflection layer 41 ) is irradiated with near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 and reflected by the reflection film 41 , and the phosphor 30 emits white light as shown by arrows B in FIG. 1 .
  • the anode electrode 14 and the cathode electrode 15 are metal electrodes composed of gold, aluminum, or layered metal electrodes composed of gold or aluminum layered with nickel, titan or the like.
  • the anode electrode 14 and the cathode electrode 15 are respectively connected to an anode and a cathode of each LED 11 .
  • the anode wiring 12 and the cathode wiring 13 are metal wirings composed of gold, aluminum, or layered metal wirings composed of gold or aluminum layered with nickel, titan or the like.
  • the anode wiring 12 and the cathode wiring 13 are respectively connected to the anode electrodes 14 and the cathode electrodes 15 of the LEDs 11 .
  • An end of the anode wiring 12 is connected to the anode driver IC 31 , and an end of the cathode wiring 13 is connected to the cathode driver IC 32 , so that the anode electrodes 14 and the cathode electrodes 15 of the LEDs 11 are connected to the anode driver IC 31 and the cathode driver IC 32 via the anode wiring 12 and the cathode wiring 13 .
  • the anode driver IC 31 has a function to supply electric current to the LEDs 11 according to a lighting signal.
  • a shift register circuit, a latch circuit, a constant current circuit, an amplifier circuit and the like are integrated.
  • the anode wiring 12 is connected to the anode electrodes 14 of the LEDs 11 and is also connected to a driving element of the anode driver IC 31 .
  • the anode driver IC 31 is mounted on the substrate 10 in the example shown in FIG. 2 , the anode driver IC 31 is not necessarily mounted on the substrate 10 , but can be provided on other print circuit board (not shown) or the like.
  • the cathode driver IC 32 has a function to allow the electric current to flow therein from the LEDs 11 .
  • switching circuits such as transistor or the like are integrated.
  • the cathode wiring 13 is connected to the cathode electrodes 15 of the LEDs 11 and is also connected to the cathode driver IC 32 .
  • the cathode driver IC 32 is not necessarily provided on the substrate 10 , but can be provided on other print circuit board (not shown) or the like.
  • FIG. 6 shows a process for peeling a thin-film layered structure (the LEDs 11 ) according to the first embodiment of the present invention.
  • FIG. 7 shows a process for fixing the thin-film layered structure (the LED 11 ) to the substrate according to the first embodiment of the present invention.
  • FIG. 8 shows a process for dividing the thin-film layered structure into a plurality of LEDs 11 according to the first embodiment of the present invention.
  • reference numeral 18 indicates an elongated band-shaped (or strip-shaped) thin-film layered structure 18 .
  • the thin-film layered structure 18 is fixed to the substrate 10 and is divided into a plurality of LEDs 11 as described later.
  • the thin-film layered structure 18 emits near-ultraviolet rays or ultraviolet rays, and has heterostructure or double-heterostructure composed of a plurality of layers such as gallium nitride or indium gallium nitride, aluminum gallium nitride, aluminum nitride or the like.
  • a sacrificial layer 17 is formed between a base material 16 and the thin-film layered structure 18 for peeling (i.e., separating) the thin-film layered structure 18 from the base material 16 .
  • the sacrificial layer 17 is composed of material such as, for example, aluminum arsenide that can easily be etched by an etching solution described later.
  • the base material 16 is composed of, for example, gallium arsenide, gallium nitride, sapphire or the like.
  • Inorganic material layers (for forming thin-film layered structure 18 ) are epitaxially grown on the base material 16 using a vapor-phase growth method such as an MOCVD method.
  • each thin-film layered structure 18 is formed to have a band-shape having a width greater than or equal to 2 mm and a length greater than or equal to the column of LED array (i.e., the column including 3 LEDs 11 ).
  • the thin-film layered structure 18 is formed in a band-shape on the base material 16 using an etching solution such as a solution containing phosphoric acid, hydrogen peroxide and water (H 3 PO 4 :H 2 O 2 :H 2 O) or the like, by means of photolithographic etching technique broadly used in a semiconductor manufacturing process.
  • the base material 16 on which the thin-film layered structure 18 is formed is immersed in an etching solution such as hydrogen-fluoride solution, hydrochloric solution or the like. With this, the sacrificial layer 17 is etched, and the thin-film layered structure 18 is peeled off from the base material 16 .
  • an etching solution such as hydrogen-fluoride solution, hydrochloric solution or the like.
  • the thin-film layered structure 18 (having been peeled off from the base material 16 ) is pressed against the planarized first surface 10 a of the substrate 10 .
  • the substrate 10 and the thin-film layered structure 18 are fixed to each other by means of intermolecular force and integrated with each other.
  • the substrate 10 has the surface layer 101 (the first surface 10 a ) shown in FIG. 1 formed of an organic insulation film such as polyimide film or an inorganic insulation film such as silicon oxide firm, and whose surface accuracy is less than or equal to several tens of nanometers having no concaves or convexes. Since the surface layer 101 of the substrate 10 has such a flat surface having no concave or convex, the bonding between the thin-film layered structure 18 and the substrate 10 by means of intermolecular force (such as hydrogen bonding or the like) can be facilitated.
  • intermolecular force such as hydrogen bonding or the like
  • a plurality of (for example, three) thin-film layered structures 18 are fixed to and integrated with the first surface 10 a of the substrate 10 as shown in FIG. 7 .
  • the thin-film layered structures 18 fixed to the first surface 10 a of the substrate 10 are divided into a plurality of LEDs 11 using an etching solution such as a solution containing phosphoric acid, hydrogen peroxide and water (H 3 PO 4 :H 2 O 2 :H 2 O) or the like.
  • an etching solution such as a solution containing phosphoric acid, hydrogen peroxide and water (H 3 PO 4 :H 2 O 2 :H 2 O) or the like.
  • each thin-film layered structure 18 is divided into three LEDs 11 .
  • the LED array in which LEDs 11 are arranged on the first surface 10 a of the substrate 10 at equal intervals in a square grid and in a matrix with 3 rows and 3 columns can be obtained.
  • anode electrodes 14 and the cathode electrodes 15 (connected to the anodes and the cathodes of the LEDs 11 ), the anode wiring 12 , the cathode wiring 13 and the interconnection wiring 21 (connected to the respective anode electrodes 14 and the respective cathode electrodes 15 ) are formed using a vacuum deposition method, a photolithographic etching method or a lift-off method. Further, the anode driver IC 31 and the cathode driver IC 32 are mounted to the substrate 10 .
  • the anode electrodes 14 and the cathode electrodes 15 of the respective LEDs 11 are connected to the anode driver IC 31 and the cathode driver IC 32 via the anode wiring 12 , the cathode wiring 13 and the interconnection wiring 21 .
  • an amplifier circuit of the anode driver IC 31 applies a constant current to the anode electrodes 14 of the LEDs 11 (closest to the anode driver IC 31 in respective columns) via the anode wiring 12 .
  • the cathode driver IC 32 When the lighting signal is inputted to the cathode driver IC 32 , the cathode driver IC 32 operates to allow the current to flow therein from the cathode electrodes 15 of the LEDs 11 (farthest from the anode driver IC 31 in respective columns) via the cathode wiring 13 connected to the cathode driver IC 32 by means of a switching circuit of a large capacity.
  • the LEDs 11 of each column connected in series by interconnection wirings 21 are applied with current, and the LEDs 11 emit light.
  • the phosphor 30 and the reflection layer 41 are disposed so as to face each other on both sides of the LEDs 11 via the substrates 10 and 40 . Therefore, when the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm in response to the lighting signal, the rays proceeding toward the substrate 10 are directly incident on the phosphor 30 (as shown by the arrows A in FIG. 1 ), and the rays proceeding toward the substrate 40 are reflected by the reflection layer 41 (as shown by the arrows C in FIG. 1 ) and are incident on the phosphor 30 .
  • the phosphor 30 is excited by the near-ultraviolet rays or ultraviolet rays, and emits white light as shown by the arrows B in FIG. 1 .
  • the LCD panel 200 ( FIG. 5 ) disposed facing the LED backlight device 100 is illuminated by the light emitted by the phosphor 30 from the backside of the LCD panel 200 .
  • LEDs 11 of each column are connected in series in this embodiment, it is also possible to connect the LEDs 11 of each row in series. Further, it is also possible to connect obliquely arranged LEDs 11 in series. Further, it is also possible to drive LEDs 11 individually. It is also possible to combine LEDs 11 (connected in series) arranged in a row or column, arranged obliquely or various other way.
  • the substrates 10 and 40 are fixed to each other so that the first surface 10 a of the substrate 10 (to which the LEDs 11 are fixed) faces the first surface 40 a of the substrate 40 .
  • the substrates 10 and 40 can be fixed to each other by filling a material such as silicone-based resin having high optical transparency into between the substrates 10 and 40 , deforming the material, and drying the material.
  • the LEDs 11 , the anode wiring 12 and the cathode wiring 13 are formed on the substrate 10 having optical transparency, and the LEDs 11 are connected to the anode wiring 12 and the cathode wirings 13 using the semiconductor process, and therefore it becomes possible to accomplish a thin and large-size LED backlight device 100 .
  • the LEDs 11 can be formed to have a desired size and shape, and can be disposed on a predetermined position on the surface of the substrate 10 . Further, the phosphor 30 and the reflection layer 41 are disposed so as to face each other on both sides of the LEDs 11 via the substrates 10 and 40 . With such a configuration, a variation in brightness can be restricted by adjusting the shapes and positions of LEDs 11 and thicknesses of the substrates 10 and 41 . Moreover, both of the light emitted by the LEDs 11 toward the substrate 10 and the light emitted by the LEDs 11 toward the substrate 40 can be used to excite the phosphor 30 , and therefore the entire brightness can be enhanced.
  • FIG. 9 is a side sectional view showing the LED backlight device according to the second embodiment of the present invention.
  • FIG. 10 is a perspective view showing the LED backlight device according to the second embodiment of the present invention, as seen from the first surface side thereof.
  • the LED backlight device 300 of the second embodiment includes a substrate 10 (as a first substrate) and a substrate 50 (as a second substrate) each of which is in the form of a flat plate.
  • the substrate 10 has a first surface 10 a (i.e., an upper surface in FIG. 9 ) and a second surface 10 b (i.e., a lower surface in FIG. 9 ) as was described in the first embodiment.
  • the substrate 50 has a first surface 50 a (i.e., a lower surface in FIG. 9 ) facing the substrate 10 and a second surface 50 b (i.e., an upper surface in FIG. 9 ).
  • a plurality of LEDs 11 are arranged on the first surface 10 a of the substrate 10 .
  • a plurality of protrusions 52 are formed on the first surface 50 a of the substrate 50 .
  • the protrusions 52 have inclined surfaces 52 a which are inclined with respect to flat portions of the first surface 50 a of the substrate 50 .
  • a reflection layer 51 is fixed to the first surface 50 a and the protrusions 52 of the substrate 50 so as to entirely cover the first surface 50 a .
  • the first surface 10 a of the substrate 10 and the first surface 50 a of the substrate 50 face each other.
  • Each protrusion 52 of the substrate 50 is disposed so as to face a center position between adjacent LEDs 11 on the first surface 10 a of the substrate 10 .
  • the apexes of the protrusions 52 contact the first surface 10 a of the substrate 10 .
  • the protrusions 52 are formed in a grid pattern so as to surround respective spaces in which LEDs 11 ( FIG. 9 ) are disposed.
  • the LEDs 11 on the first surface 10 a and the phosphor 30 on the second surface 10 b of the substrate 10 face each other. Further, the LEDs 11 on the first surface 10 a of the substrate 10 and the reflection layer 51 on flat portions of the first surface 50 a of the substrate 50 face each other.
  • the phosphor 30 on the second surface 10 b of the substrate 10 and the reflection layer 51 on flat portions of the first surface 50 a of the substrate 50 face each other on both sides of the LEDs 11 via the substrates 10 and 50 .
  • the light emitted by the LEDs 11 in the direction toward the substrate 10 is incident on the phosphor 30 as shown by arrows A in FIG. 9 .
  • the light emitted by the LEDs 11 in the direction toward the substrate 50 is reflected by the reflection layer 51 on the flat portions of the first surface 50 a of the substrate 50 , and is incident on the phosphor 30 as shown by arrows C in FIG. 9 .
  • the protrusions 52 have inclined surfaces 52 a and the reflection surface 51 is also formed on the inclined surfaces 52 a . Therefore, the light emitted by peripheral end surfaces of the LEDs 11 is reflected by the reflection layer 51 on the inclined surfaces 52 a of the protrusions 52 at angles corresponding to the inclination angles of the inclined surfaces 52 a.
  • the lights emitted by the LEDs 11 indicated by arrows A, C and D are near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm.
  • the phosphor 30 is irradiated with near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 and reflected by the reflection layer 51 , and emits white light as shown in arrows B in FIG. 9 .
  • the other components of the LED backlight device 300 and the LCD device are the same as those described in the first embodiment, and therefore duplicate descriptions are omitted.
  • the amplifier circuit of the anode driver IC 31 applies a constant current to the anode electrodes 14 of the LEDs 11 closest to the anode driver IC 31 in respective columns via the anode wiring 12 .
  • the cathode driver IC 32 operates to allow the current to flow therein from the cathode electrodes 15 of the LEDs 11 farthest from the anode driver IC 31 in respective columns via the cathode wiring 13 connected to the cathode driver IC 32 by means of the switching circuit of a large capacity.
  • the LEDs 11 of each column connected in series by interconnection wirings 21 are applied with current, and the LEDs 11 emit light.
  • the phosphor 30 and the reflection layer 51 are disposed so as to face each other on both sides of the LEDs 11 via the substrates 10 and 50 . Therefore, when the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm in response to the lighting signal, the rays proceeding toward the substrate 10 are directly incident on the phosphor 30 (as shown by the arrows A in FIG. 9 ), and the rays proceeding toward the substrate 50 is reflected by the reflection layer 51 (as shown by the arrows C in FIG. 1 ) and is incident on the phosphor 30 .
  • the light emitted from the peripheral end surfaces of the LEDs 11 (indicated by arrows D in FIG. 9 ) is reflected by the reflection layer 51 on the inclined surface 52 a of each protrusion 52 at an angle corresponding to the inclination of the inclined surface 52 a , and is incident on the phosphor 30 .
  • the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm from both surfaces and peripheral end surfaces of the LEDs 11
  • the phosphor 30 is excited by the near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 or reflected by the reflection layer 51 , and emits white light as shown by the arrows B in FIG. 9 .
  • the LCD panel 200 ( FIG. 5 ) disposed facing the LED backlight device 300 is illuminated by the light emitted by the phosphor 30 from the backside of the LCD panel 200 .
  • the above described substrates 10 and 50 are fixed to each other so that the first surface 10 a of the substrate 10 faces the first surface 50 a of the substrate 50 and the protrusions 52 (to which the reflection layer 51 is fixed) contact the first surface 10 a of the substrate 10 at positions between the adjacent LEDs 11 .
  • the substrates 10 and 50 can be fixed to each other by filling a material such as silicone-based resin having high optical transparency into between the substrates 10 and 50 , deforming the material, and drying the material.
  • the phosphor 30 and the reflection layer 51 are disposed so as to face each other on both sides of the LEDs 11 via the substrates 10 and 50 . Further, the protrusions 52 contact the first surface 10 a of the substrate 10 at positions between the adjacent LEDs 11 , and the reflection layer 51 is fixed to the inclined surfaces 52 a of the protrusions 52 . Therefore, the light emitted by the peripheral end surfaces of the LEDs 11 is reflected by the reflection layer 51 on the protrusions 52 , and is incident on the phosphor 30 . Accordingly, the phosphor 30 is irradiated with the light emitted by the peripheral end surfaces of the LEDs 11 , as well as the light emitted by both surfaces of the LEDs 11 . As a result, a thin and large-size LED backlight device having enhanced brightness can be obtained.
  • FIG. 11 is a side sectional view showing the LED backlight device according to the third embodiment of the present invention.
  • FIG. 12 is a perspective view showing a first substrate of the LED backlight device according to the third embodiment of the present invention, as seen from the first surface side thereof.
  • the LED backlight device 400 includes a substrate 10 (i.e., a first substrate) and a substrate 40 (i.e., a second substrate) each of which is in the form of a flat plate.
  • the substrate 10 has a first surface 10 a (i.e., an upper surface in FIG. 11 ) and a second surface 10 b (i.e., a lower surface in FIG. 11 ) as was described in the first embodiment.
  • the substrate 40 has a first surface 40 a (i.e., a lower surface in FIG. 11 ) facing the substrate 10 and a second surface 40 b (i.e., an upper surface in FIG. 11 ).
  • the first surface 10 a of the substrate 10 and the first surface 40 a of the substrate 40 face each other.
  • a plurality of LEDs 11 are arranged on the first surface 10 a of the substrate 10 .
  • a reflection layer 41 is fixed to the second surface 40 b of the substrate 40 so as to entirely cover the second surface 40 b .
  • a plurality of protrusions 19 are formed on the first surface 10 a of the substrate 10 .
  • the protrusions 19 protrude toward the substrate 40 and have inclined surfaces 19 a .
  • Each protrusion 19 is disposed on a center position between adjacent LEDs 11 . Tips (apexes) of the protrusions 19 contact the first surface 40 a of the substrate 40 in a state where the substrate 10 and the substrate 40 face each other.
  • the protrusions 19 are composed of material that reflects the light (in this example, near-ultraviolet rays or ultraviolet rays).
  • the protrusions 19 are formed in a grid pattern so as to surround respective spaces in which LEDs 11 are disposed.
  • the LEDs 11 and the phosphor 30 are respectively provided on the first and second surfaces 10 a and 10 b of the substrate 10 so that the LEDs 11 and the phosphors 30 face each other.
  • the LEDs 11 and the reflection layer 41 are respectively provided on the first surface 10 a of the substrate 10 and the second surface 40 b of the substrate 40 so that the LEDs 11 and the reflection layer 41 face each other.
  • the phosphor 30 and the reflection layer 41 face each other on both sides of the LEDs 11 .
  • the light emitted by the LEDs 11 toward the substrate 10 is directly incident on the phosphor 30 as shown by arrows A in FIG. 11 .
  • the light emitted by the LEDs 11 is reflected by the reflection layer 41 on the first surface 10 a of the substrate 10 as shown by arrows C in FIG. 11 , and is incident on the phosphor 30 .
  • the protrusions 19 have inclined surface 19 a , the light emitted by the peripheral end surfaces of the LEDs 11 is reflected by the inclined surfaces 19 a of the protrusions 19 (as shown by arrows D in FIG. 11 ) at angles corresponding to the inclinations of the inclined surfaces 19 a , is further reflected by the reflection layer 41 of the substrate 40 , and is incident on the phosphor 30 .
  • the light emitted by the LEDs 11 indicated by arrows A, C and D is near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm.
  • the phosphor 30 is irradiated with the near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 or reflected by the reflection layer 41 , and emits white light as shown by arrows B.
  • the other components of the LED backlight device 400 and the LCD device are the same as those described in the first or second embodiment, and therefore duplicate descriptions are omitted.
  • the amplifier circuit of the anode driver IC 31 applies a constant current to the anode electrodes 14 of the LEDs 11 closest to the anode driver IC 31 in respective columns via the anode wiring 12 .
  • the cathode driver IC 32 operates to allow the current to flow therein from the cathode electrodes 15 of the LEDs 11 farthest from the anode driver IC 31 in respective columns via the cathode wiring 13 connected to the cathode driver IC 32 by means of the switching circuit of a large capacity.
  • the LEDs 11 of each column connected in series by interconnection wirings 21 are applied with current, and the LEDs 11 emit light.
  • the phosphor 30 and the reflection layer 41 are disposed so as to face each other on both sides of the LEDs 11 . Therefore, when the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm, the rays proceeding toward the substrate 10 is directly incident on the phosphor 30 (as shown by the arrows A in FIG. 11 ), and the rays proceeding toward the substrate 40 is reflected by the reflection layer 41 (as shown by the arrows C in FIG. 11 ) and is incident on the phosphor 30 .
  • the protrusions 19 have inclined surfaces 19 a , the rays emitted by the peripheral end surfaces of the LEDs 11 are reflected by the inclined surfaces 19 a of the protrusions 19 (as shown by the arrows D in FIG. 11 ) at angles corresponding to the inclinations of the inclined surfaces 19 a , are further reflected by the reflection layer 41 of the substrate 40 , and are incident on the phosphor 30 .
  • the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm from both surfaces and peripheral end surfaces of the LEDs 11
  • the phosphor 30 is excited by the near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 and reflected by the reflection layer 41 , and emits white light as shown by the arrows B in FIG. 11 .
  • the LCD panel 200 ( FIG. 5 ) disposed facing the LED backlight device 400 is illuminated by the light emitted by the phosphor 30 from the backside of the LCD panel 200 .
  • the above described substrates 10 and 40 are fixed to each other so that the first surface 10 a of the substrate 10 faces the first surface 40 a of the substrate 40 and the tips of the protrusions 19 contact the first surface 40 a of the substrate 40 .
  • the substrates 10 and 40 can be fixed to each other by filling a material such as silicone-based resin having high optical transparency into between the substrates 10 and 40 , deforming the material, and drying the material.
  • the phosphor 30 and the reflection layer 41 are disposed so as to face each other on both sides of the LEDs 11 , and the protrusions 19 (each of which is disposed on the center position between the adjacent LEDs 11 ) have inclined surfaces 19 a . Therefore, the light emitted by the peripheral end surfaces of the LEDs 11 is reflected by the inclined surfaces 19 a of the protrusions 19 , and is incident on the phosphor 30 . Accordingly, the phosphor 30 is irradiated with the light emitted by the peripheral end surfaces of the LEDs 11 , as well as the light emitted by both surfaces of the LEDs 11 . As a result, a thin and large-size LED backlight device having enhanced brightness can be obtained.
  • FIG. 13 is a side sectional view showing the LED backlight device according to the fourth embodiment of the present invention.
  • FIG. 14 is a perspective view showing a first substrate of the LED backlight device according to the fourth embodiment of the present invention, as seen from the first surface side.
  • FIG. 15 is a perspective view showing a second substrate of the LED backlight device according to the fourth embodiment of the present invention, as seen from the first surface side.
  • the LED backlight device 500 includes a substrate 10 (i.e., a first substrate) and a substrate 60 (i.e., a second substrate) each of which is in the form of a flat plate.
  • the substrate 10 has a first surface 10 a (i.e., an upper surface in FIG. 13 ) and a second surface 10 b (i.e., a lower surface in FIG. 13 ).
  • the substrate 60 has a first surface 60 a (i.e., a lower surface) 60 a facing the substrate 10 and a second surface 60 b (i.e., an upper surface).
  • the first surface 10 a of the substrate 10 and the first surface 60 a of the substrate 60 face each other.
  • a plurality of LEDs 11 are arranged on the first surface 10 a of the substrate 10 .
  • a reflection layer 61 is fixed to the second surface 60 b of the substrate 60 so as to entirely cover the second surface 60 b .
  • a plurality of protrusions 20 are formed on the first surface 10 a of the substrate 10 .
  • the protrusions 20 have inclined surfaces 20 a . As shown in FIG. 14 , the protrusions 20 are formed so as to surround the respective LEDs 11 on the first surface 10 a of the substrate 10 .
  • a plurality of concaves 62 are formed on the second surface 60 b of the substrate 60 .
  • the concaves 62 have depths toward the first surface 60 a of the substrate 60 , and have inclined surfaces 62 a .
  • a reflection layer 61 is fixed to the second surface 60 b of the substrate 60 including the inclined surfaces 62 a of the concaves 62 .
  • the first surface 10 a of the substrate 10 and the first surface 60 a of the substrate 60 face each other.
  • Each concave 62 is disposed at a center position between the adjacent LEDs 11 on the first surface 10 a of the substrate 10 .
  • the protrusions 20 are formed of material such as Aluminum or the like that reflects the light (in this example, near-ultraviolet rays or ultraviolet rays).
  • the LEDs 11 and the phosphor 30 are respectively formed on the first and second surfaces 10 a and 10 b of the substrate 10 so that LEDs 11 and phosphor 30 face each other.
  • the LEDs 11 and the reflection surface 61 are respectively formed on the first surface 10 a of the substrate 10 and the second surface 60 b of the substrate 60 so that the LEDs 11 and the reflection layer 61 face each other.
  • the phosphor 30 and the reflection layer 61 face each other on both sides of the LEDs 11 . Therefore, the light emitted by the LEDs 11 in the direction toward the substrate 10 is incident on the phosphor 30 as shown by arrow A in FIG. 13 . Further, the light emitted by the LEDs 11 is reflected by the reflection layer 61 on the second surface 60 b of the substrate 60 as shown by arrows C, and is incident on the phosphor 30 .
  • the protrusions 20 have inclined surface 20 a , the light emitted by the peripheral end surfaces of the LEDs 11 is reflected by the inclined surfaces 20 a of the protrusions 20 (as shown by arrows D) at angles corresponding to the inclinations of the inclined surfaces 20 a , is further reflected by the reflection layer 61 of the substrate 60 , and is incident on the phosphor 30 .
  • the concaves 62 have inclined surfaces 62 a , part of the light emitted by the LEDs 11 in the direction toward the substrate 60 is reflected by the reflection layer 61 on the inclined surfaces 62 a (as shown by arrows E) at angles corresponding to the inclinations of the inclined surfaces 20 a , and is incident on the phosphor 30 .
  • the light emitted by the LEDs 11 indicated by arrows A, C, D and E is near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm.
  • the phosphor 30 is irradiated with the near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 or reflected by the reflection layer 61 , and emits white light as shown by arrows B.
  • the other components of the LED backlight device 500 and the LCD device are the same as those described in the first, second or third embodiment, and therefore duplicate descriptions are omitted.
  • the amplifier circuit of the anode driver IC 31 applies a constant current to the anode electrodes 14 of the LEDs 11 closest to the anode driver IC 31 in respective columns via the anode wiring 12 .
  • the cathode driver IC 32 operates to allow the current to flow therein from the cathode electrodes 15 of the LEDs 11 farthest from the anode driver IC 31 in respective columns via the cathode wiring 13 connected to the cathode driver IC 32 by means of the switching circuit of a large capacity.
  • the LEDs 11 of each column connected in series by interconnection wirings 21 are applied with current, and the LEDs 11 emit light.
  • the phosphor 30 and the reflection layer 61 are disposed so as to face each other on both sides of the LEDs 11 . Therefore, when the LEDs 11 emit near-ultraviolet rays or ultraviolet rays having the wavelength in the range from 300 to 450 nm, the rays proceeding toward the substrate 10 is directly incident on the phosphor 30 (as shown by the arrows A), and the rays proceeding toward the substrate 60 is reflected by the reflection layer 61 (as shown by the arrows C) and is incident on the phosphor 30 .
  • the protrusions 20 have inclined surface 20 a , the rays emitted by the peripheral end surfaces of the LEDs 11 are reflected by the inclined surfaces 20 a of the protrusions 20 at angles corresponding to the inclinations of the inclined surfaces 20 a , are reflected by the reflection layer 61 of the substrate 60 and are incident on the phosphor 30 as shown by the arrows D.
  • the concaves 62 have inclined surface 62 a , part of the rays emitted by the LEDs 11 toward the substrate 60 is reflected by the reflection layer 61 on the inclined surfaces 62 a at angles corresponding to the inclinations of the inclined surfaces 62 a , and is incident on the phosphor 30 as shown by the arrows E.
  • the phosphor 30 is excited by the near-ultraviolet rays or ultraviolet rays directly proceeding from the LEDs 11 or reflected by the reflection layer 61 , and emits white light as shown by the arrows B in FIG. 13 .
  • the LCD panel 200 ( FIG. 5 ) disposed facing the LED backlight device 500 is illuminated by the light emitted by the phosphor 30 from the backside of the LCD panel 200 .
  • the above described substrates 10 and 60 are fixed to each other so that the first surface 10 a of the substrate 10 faces the first surface 60 a of the substrate 60 and the tips of the protrusions 20 contact the first surface 60 a of the substrate 60 .
  • the substrates 10 and 60 can be fixed to each other by filling a material such as silicone-based resin having high optical transparency into between the substrates 10 and 60 , deforming the material, and drying the material.
  • the phosphor 30 and the reflection layer 61 are disposed so as to face each other on both sides of the LEDs 11 , and the protrusions 20 with inclined surfaces 20 a surround the respective LEDs 11 .
  • the concaves 62 (to which the reflection layer 61 is fixed) have inclined surfaces 62 a . Therefore, the light emitted by the peripheral end surfaces of the LEDs 11 is reflected by the protrusions 20 , and is incident on the phosphor 30 . Further, part of the light emitted by the LEDs 11 is reflected by the reflection layer 61 on the inclined surfaces 62 a of the concaves 62 , and is incident on the phosphor 30 .
  • the phosphor 30 is irradiated with the light emitted by the peripheral end surfaces of the LEDs 11 , as well as the light emitted by both surfaces of the LEDs 11 .
  • a thin and large-size LED backlight device can be obtained.

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US20090161039A1 (en) * 2007-12-25 2009-06-25 Oki Dara Corporation LED backlight device and LCD device
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US8384114B2 (en) 2009-06-27 2013-02-26 Cooledge Lighting Inc. High efficiency LEDs and LED lamps
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Citations (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09232198A (ja) 1996-02-27 1997-09-05 Kyocera Corp 半導体基板の製造方法
WO1997048138A2 (en) 1996-06-11 1997-12-18 Philips Electronics N.V. Visible light emitting devices including uv-light emitting diode and uv-excitable, visible light emitting phosphor, and method of producing such devices
US5813753A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue led-phosphor device with efficient conversion of UV/blues light to visible light
JPH11232920A (ja) 1998-02-13 1999-08-27 Omron Corp 面光源装置及び同装置用の光取り込み口モジュール
JP2000133006A (ja) 1998-10-29 2000-05-12 Sanyo Electric Co Ltd 面光源
US20030026096A1 (en) 2001-07-31 2003-02-06 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh LED-based planar light source
JP2003068109A (ja) 2001-08-23 2003-03-07 Sony Corp 照明装置及び投影装置
EP1385215A2 (en) 2002-07-08 2004-01-28 Nichia Corporation Nitride semiconductor device comprising bonded substrate and fabrication method of the same
US20040021629A1 (en) 2002-07-18 2004-02-05 Citizen Electronics Co., Ltd. Light emitting diode device
JP2004119634A (ja) 2002-09-25 2004-04-15 Toshiba Lighting & Technology Corp 発光装置
JP2005051117A (ja) 2003-07-30 2005-02-24 Oki Data Corp 半導体装置の製造方法
JP2005079369A (ja) 2003-09-01 2005-03-24 Oki Data Corp 半導体複合装置の製造方法
EP1521235A2 (en) 2003-10-03 2005-04-06 LumiLeds Lighting U.S., LLC Liquid crystal display backlight with a two-dimensional array of light emitting diodes
JP2005093649A (ja) 2003-09-17 2005-04-07 Oki Data Corp 半導体複合装置、ｌｅｄプリントヘッド、及び、それを用いた画像形成装置
JP2005150703A (ja) 2003-10-22 2005-06-09 Oki Data Corp 半導体装置、及び、それを用いたｌｅｄプリントヘッド、画像形成装置、半導体装置の製造方法
US7006172B2 (en) * 2002-08-30 2006-02-28 Mitsubishi Chemical Corporation Color liquid crystal display devices
US20060158581A1 (en) 1997-05-16 2006-07-20 Kabushiki Kaisha Toshiba Image display device and light emission device
WO2006076210A2 (en) 2005-01-11 2006-07-20 Semileds Corporation Systems and methods for producing white-light light emitting diodes
JP2006244779A (ja) 2005-03-01 2006-09-14 Matsushita Electric Works Ltd 照明光源、照明装置、及び表示装置
JP2006261218A (ja) 2005-03-15 2006-09-28 Oki Data Corp 半導体装置、半導体ユニット、ｌｅｄヘッド及び画像形成装置
JP2006308858A (ja) 2005-04-28 2006-11-09 Mitsubishi Chemicals Corp 表示装置
US20070080626A1 (en) * 2005-10-11 2007-04-12 Seung-Hyun Son Light emitting device using electron emission and flat display apparatus using the same
US7481563B2 (en) 2006-09-21 2009-01-27 3M Innovative Properties Company LED backlight

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07228003A (ja) * 1993-12-22 1995-08-29 Kyocera Corp 画像装置
JP3460330B2 (ja) * 1994-08-31 2003-10-27 京セラ株式会社 画像装置
JPH1041546A (ja) * 1996-07-22 1998-02-13 Nippon Sanso Kk 発光素子
JPH10335706A (ja) * 1997-05-30 1998-12-18 Toyoda Gosei Co Ltd 発光ダイオードランプ
JP3454123B2 (ja) * 1997-11-25 2003-10-06 松下電工株式会社 Ｌｅｄ照明モジュール
JP2000091628A (ja) * 1998-09-09 2000-03-31 Murata Mfg Co Ltd 半導体発光素子
JP3398638B2 (ja) * 2000-01-28 2003-04-21 科学技術振興事業団 発光ダイオードおよび半導体レーザーとそれらの製造方法
JP2002324919A (ja) * 2001-02-26 2002-11-08 Sharp Corp 発光ダイオードおよびその製造方法
JP4557542B2 (ja) * 2003-12-24 2010-10-06 ▲さん▼圓光電股▲ふん▼有限公司 窒化物発光装置及び高発光効率窒化物発光装置
JP4516337B2 (ja) * 2004-03-25 2010-08-04 シチズン電子株式会社 半導体発光装置
JP4837295B2 (ja) * 2005-03-02 2011-12-14 株式会社沖データ 半導体装置、ｌｅｄ装置、ｌｅｄヘッド、及び画像形成装置
KR20080037734A (ko) * 2005-08-23 2008-04-30 가부시끼가이샤 도시바 발광 장치와 그를 이용한 백 라이트 및 액정 표시 장치
JP4899431B2 (ja) * 2005-11-12 2012-03-21 日亜化学工業株式会社 窒化物系蛍光体及びそれを用いた発光装置

Patent Citations (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09232198A (ja) 1996-02-27 1997-09-05 Kyocera Corp 半導体基板の製造方法
WO1997048138A2 (en) 1996-06-11 1997-12-18 Philips Electronics N.V. Visible light emitting devices including uv-light emitting diode and uv-excitable, visible light emitting phosphor, and method of producing such devices
US20060158581A1 (en) 1997-05-16 2006-07-20 Kabushiki Kaisha Toshiba Image display device and light emission device
US5813753A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue led-phosphor device with efficient conversion of UV/blues light to visible light
JPH11232920A (ja) 1998-02-13 1999-08-27 Omron Corp 面光源装置及び同装置用の光取り込み口モジュール
JP2000133006A (ja) 1998-10-29 2000-05-12 Sanyo Electric Co Ltd 面光源
US20030026096A1 (en) 2001-07-31 2003-02-06 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh LED-based planar light source
JP2003068109A (ja) 2001-08-23 2003-03-07 Sony Corp 照明装置及び投影装置
EP1385215A2 (en) 2002-07-08 2004-01-28 Nichia Corporation Nitride semiconductor device comprising bonded substrate and fabrication method of the same
US20040021629A1 (en) 2002-07-18 2004-02-05 Citizen Electronics Co., Ltd. Light emitting diode device
US7006172B2 (en) * 2002-08-30 2006-02-28 Mitsubishi Chemical Corporation Color liquid crystal display devices
JP2004119634A (ja) 2002-09-25 2004-04-15 Toshiba Lighting & Technology Corp 発光装置
JP2005051117A (ja) 2003-07-30 2005-02-24 Oki Data Corp 半導体装置の製造方法
JP2005079369A (ja) 2003-09-01 2005-03-24 Oki Data Corp 半導体複合装置の製造方法
JP2005093649A (ja) 2003-09-17 2005-04-07 Oki Data Corp 半導体複合装置、ｌｅｄプリントヘッド、及び、それを用いた画像形成装置
EP1521235A2 (en) 2003-10-03 2005-04-06 LumiLeds Lighting U.S., LLC Liquid crystal display backlight with a two-dimensional array of light emitting diodes
JP2005150703A (ja) 2003-10-22 2005-06-09 Oki Data Corp 半導体装置、及び、それを用いたｌｅｄプリントヘッド、画像形成装置、半導体装置の製造方法
WO2006076210A2 (en) 2005-01-11 2006-07-20 Semileds Corporation Systems and methods for producing white-light light emitting diodes
JP2006244779A (ja) 2005-03-01 2006-09-14 Matsushita Electric Works Ltd 照明光源、照明装置、及び表示装置
JP2006261218A (ja) 2005-03-15 2006-09-28 Oki Data Corp 半導体装置、半導体ユニット、ｌｅｄヘッド及び画像形成装置
JP2006308858A (ja) 2005-04-28 2006-11-09 Mitsubishi Chemicals Corp 表示装置
US20070080626A1 (en) * 2005-10-11 2007-04-12 Seung-Hyun Son Light emitting device using electron emission and flat display apparatus using the same
US7481563B2 (en) 2006-09-21 2009-01-27 3M Innovative Properties Company LED backlight

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Akihiko Murai et al., "Hexagonal pyramid shaped light-emitting diodes based on ZnO and GaN direct wafer bonding", Applied Physics Letters 89. 171116 (2006), p. 171116-1 to 171116-3.
Po-Chun Liu et al., "Wafer bonding for high-brightness light-emitting diodes via indium tin oxide intermediate layers", Thin Solid Films 478 (2005) 280-285.

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